Java使用 jsch 连接FTP服务器操作文件

本文链接：https://blog.youkuaiyun.com/m0_69526086/article/details/124643658

本文展示了如何在Java中使用jsch库连接到FTP服务器并进行文件操作。通过建立SSH连接，创建SFTP通道，实现文件的下载等功能。文章详细讲解了配置类和工具类的实现，并提供了异常处理机制。

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session.connect();

} catch (JSchException e) {

log.error(“ssh connecting " + sshProperties.getUsername() + “@” + sshProperties.getHost() + " failed.”, e);

throw new SftpException();

}

ChannelSftp sftp;

try {

sftp = (ChannelSftp) session.openChannel(“sftp”);

sftp.connect();

} catch (JSchException e) {

log.error(“channel opens fail”, e);

throw new SftpException();

}

return sftp;

}

// 使用配置类获取操作句柄

ChannelSftp sftp = sshConfiguration.getSftp();

// 使用后关闭连接

try {

// 文件的各种操作

} catch (com.jcraft.jsch.SftpException e) {

throw new SftpException(e.getMessage());

} finally {

// 注意这里的连接关闭

sftp.disconnect();

try {

sftp.getSession().disconnect();

} catch (JSchException e) {

log.error(“sftp fails to channel get session”);

}

[](()实战演练

====================================================================

[](()配置类

package com.sduoj.judgeserver.conf;

import com.jcraft.jsch.*;

import com.sduoj.judgeserver.exception.internal.SftpException;

import lombok.Getter;

import lombok.extern.slf4j.Slf4j;

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.context.annotation.Configuration;

/**

@Author: Song yang Ji
@ProjectName: sduoj-judge-server
@Version 1.0
@Description: SFTP的配置信息类

@Configuration

@Slf4j(topic = “SFTP”)

public class SshConfiguration {

@Getter

SshProperties sshProperties;

@Autowired

public SshConfiguration(SshProperties sshProperties) {

this.sshProperties = sshProperties;

}

public ChannelSftp getSftp() throws SftpException {

Session session;

try {

session = new JSch().getSession(sshProperties.getUsername(), sshProperties.getHost(), sshProperties.getPort());

session.setConfig(“StrictHostKeyChecking”, “no”);

session.setPassword(sshProperties.getPassword());

session.connect();

} catch (JSchException e) {

log.error(“ssh connecting " + sshProperties.getUsername() + “@” + sshProperties.getHost() + " failed.”, e);

throw new SftpException();

}

ChannelSftp sftp;

try {

sftp = (ChannelSftp) session.openChannel(“sftp”);

sftp.connect();

} catch (JSchException e) {

log.error(“channel opens fail”, e);

throw new SftpException();

}

return sftp;

}

[](()工具类

接口类

package com.sduoj.judgeserver.util.sftp;

import java.nio.file.Path;

/**

@Author: Song yang Ji
@ProjectName: sduoj-judge-server
@Version 1.0
@Description:

public interface SftpFilesService {

/**

@param problemID 题目ID
@param local 下载的本地的路径
@throws SftpException Sftp 异常

void downloadProblemIOFiles(String problemID, Path local) throws SftpException;

/**

@param problemID 题目ID
@param testPointID 测试点ID
@param local 下载的本地的路径
@throws SftpException Sftp 异常

void downloadProblemTestPointIOFiles(String problemID, String testPointID, Path local) throws SftpException;

}

实现类

@Service(“sftpFilesService”)

@Slf4j(topic = “SFTP”)

public class SftpFilesServiceImpl implements SftpFilesService {

EnvironmentConfig environmentConfig;

SshConfiguration sshConfiguration;

@Autowired

public SftpFilesServiceImpl(EnvironmentConfig environmentConfig, SshConfiguration sshConfiguration) {

this.environmentConfig = environmentConfig;

this.sshConfiguration = sshConfiguration;

}

/**

@param problemID 题目ID